El nuclear law and international treaties The laws that underpin it form a kind of silent but essential legal framework: without them, it would be impossible to use nuclear energy safely, peacefully, and with even minimal coordination between countries. Although it sometimes seems like a world reserved for technicians and diplomats, behind it lie very specific rules about how nuclear power plants should operate, who is responsible in the event of an accident, and what controls are in place to prevent the proliferation of weapons.
In recent decades a network of conventions, protocols and agreements which ranges from the physical protection of nuclear material This includes everything from financial compensation for damages to facility safety and non-proliferation. Organizations such as the IAEA, the NEA, and Euratom are the key players in this supranational framework, which also coexists with domestic legislation and the technological evolution of nuclear power plants that now operate well beyond the 30 or 40 years that were once considered typical.
What is nuclear law and why does it need international treaties
When we talk about nuclear law, we are referring to set of rules that regulate peaceful uses Nuclear energy: how a power plant is designed and operated, what safety levels are required, how waste is managed, what controls prevent diversion to military uses, and who pays for damages in the event of an accident. Due to the very nature of nuclear energy, no single state can effectively regulate it in isolation.
Radiological risks They cross borders without asking permissionThe trade in fuel and equipment is global, and the non-proliferation of nuclear weapons only makes sense if it is coordinated internationally. Hence, a network of treaties has been established that sets common standards and, in many cases, imposes very specific obligations on the states that sign them.
This international nuclear law is structured around several key organizations: the International Atomic Energy Agency (IAEA) and the OECD's Nuclear Energy Agency (NEA) at the global level, and, at the European level, the European Atomic Energy Community (Euratom). Each promotes and manages its own legal instruments, but the underlying logic is shared: to harmonize rules and strengthen legal and technical certainty throughout the nuclear cycle.
In that context, the classic notion of the “useful life” of a power plant—which for years was almost automatically associated with terms close to 40 years— has been overwhelmed. Today, numerous countries, both European and the United States, are authorizing what is known as long-term operation or Long Term Operation (LTO)allowing facilities built more than three decades ago to continue operating under demanding safety criteria.
This change in perspective has forced a review, reinterpretation, and sometimes adaptation of current nuclear law, so that security regimes, civil liability and regulatory control remain effective even when the power plants far exceed the time horizons for which they were initially intended.
The IAEA's role in nuclear law treaties
The IAEA is, in practice, the epicenter of international nuclear lawUnder its auspices, some of the most important legal instruments have been negotiated, from security agreements to treaties on civil liability. The Organization not only acts as a diplomatic forum, but also as the depository for many of these agreements and as the guarantor of their day-to-day operation.
The treaties related to the work of the IAEA cover the full spectrum of relevant issues: internal organization of the OrganizationTechnological and physical security of facilities, safeguards and non-proliferation regimes, as well as civil liability systems for nuclear damage. To manage them, the IAEA classifies them into three main categories, based on their legal relationship with them.
Types of treaties related to the IAEA
The first large group are the treaties under the auspices of the IAEAThese are international agreements that member states negotiate and conclude within the framework of the Agency, with the support of its Secretariat, and for which the Director General acts as the official depositary. This means that the IAEA holds the authentic texts, receives the instruments of ratification, accession, or acceptance, and notifies the states and the United Nations of the legal status of each treaty.
In this package we find fundamental agreements such as the Convention on Nuclear SafetyThis includes the Convention on the Physical Protection of Nuclear Material and its Amendment, which establishes obligations regarding the design, construction, operation, and decommissioning of facilities, and the Convention on the Physical Protection of Nuclear Material and its Amendment, which sets minimum requirements to prevent theft, sabotage, or misuse of nuclear material. Also included here are various conventions on civil liability for nuclear damage, which are discussed in more detail later.
The second group consists of the agreements to which the IAEA itself is a partyIn this case, the Agency acts as a subject of international law and enters into treaties with specific States or other organizations. These agreements confer upon it both direct rights and obligations. Typical examples include the Headquarters Agreement with Austria, which governs the IAEA's status in Vienna, and the Agreement on Relations between the United Nations and the IAEA, which defines their institutional relationship.
This category also includes the safeguards agreementswhich allow the IAEA to verify that the nuclear materials and activities declared by States are not diverted from peaceful purposes, as well as numerous technical cooperation agreements that channel assistance for the development of safe civil nuclear programs.
The third group includes the so-called treaties related to the IAEAThese are international agreements that were not concluded under its auspices or with its direct participation as a party, but which are fully relevant to its mandate. In many cases, these agreements assign it specific verification or technical support functions. The most representative example is the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), along with various regional non-proliferation treaties that also fall within the scope of the Agency's work.
Civil liability for nuclear damage and the INLEX group
One of the most sensitive areas of nuclear law is that relating to the liability for nuclear damageExperiences with major accidents have shown that, without a clear and predictable framework, both victims and operators operate in a highly uncertain environment. To avoid this, several international agreements have been established that determine who pays, how much, and under what conditions.
The IAEA's Nuclear Law and Treaty Section bears primary responsibility for the instruments developed under its auspices in this area. These include the following: Vienna Convention on Civil Liability for Nuclear Damage, which establishes a regime based on the strict liability of the operator of the installation, the Common Protocol relating to the Application of the Vienna Convention and the Paris Convention, which links two distinct regional systems, and the Protocol Amending the Vienna Convention, which updates limits and conditions.
These instruments are in addition to the Convention on Supplementary Compensation for Nuclear Damage, designed to establish an additional compensation mechanism financed by the Parties, so that the available economic resources are strengthened when the magnitude of the damage exceeds the threshold covered at the national level.
In this context, the Nuclear Law and Treaty Section also manages the Secretariat of the International Group of Experts on Liability for Nuclear Damage (INLEX)Created in 2003 by the Director General of the IAEA, this group advises on the interpretation of conventions, promotes their accession, and helps States adapt their domestic legislation to be consistent with international standards.
Thanks to the work of INLEX and the IAEA, progress has been made in the practical harmonization of liability regimesreducing gaps and overlaps between systems and offering solutions for complex situations, such as accidents with cross-border effects or claims affecting several different States.
Supranational organizations: IAEA, NEA and Euratom
Several operate above the states. specialized supranational organizations that form the backbone of the legal framework for nuclear energy. At the global level, the IAEA and the OECD's Nuclear Energy Agency (NEA) stand out, while in Europe the central body is Euratom. They all share the common feature of being based on constituent treaties that are binding on their members.
These organizations have promoted, over the years, a wide range of agreements and standards that They standardize the legal framework for nuclear facilities in the various Member States. The aim is to avoid large regulatory differences that could affect safety or create distortions in the trade of nuclear materials and technology.
One particularly relevant instrument is the Convention on Nuclear Safety, adopted under the auspices of the IAEA in 1994. This convention does not limit itself to proclaiming principles, but goes into the concrete regulation of all phases of the life cycle of an installation: design, construction, commissioning, normal operation, maintenance, final closure and dismantling.
Instead of setting a rigid number of years for the useful life of a power plant, the Convention focuses on the safety criteria and case-by-case assessmentIt is the national regulatory bodies that must analyze, in light of international standards and accumulated experience, whether a power plant can continue to operate safely beyond certain theoretical dates.
The practical reality, both in the United States and in most European countries with operating nuclear power plants—with the notable exception of Germany, which has opted to phase out nuclear energy—is that so-called long-term operation is being authorized or Long Term Operation (LTO). This means that power plants built more than 30 or 35 years ago They continue to function after exhaustive security reviews, system reinforcements, and technological updates.
Euratom: The European Union's Nuclear Treaty
Within the European space, the Treaty establishing the European Atomic Energy Community, better known as Euratom TreatyIt is the cornerstone of nuclear law. Signed in Rome in 1957, together with the treaty establishing the European Economic Community, it was initially signed by the six founding countries of the European Coal and Steel Community and remains fully in force today.
Unlike other European treaties, Euratom It has not been subject to major revisions. It maintains its own legal personality, separate from the European Union, although it shares the same Member States and many of its institutions. Together with the Treaty on European Union (TEU) and the Treaty on the Functioning of the EU (TFEU), it forms part of the Union's primary law.
The scope of the Euratom Treaty is strictly limited to the civilian, non-military uses of nuclear energyThis separation is key: everything related to defense and nuclear weapons falls outside its scope, focusing on research, production and the peaceful use of atomic energy.
In its Title I, the Treaty lists eight major missions entrusted to the CommunityThese missions are developed in Title II through specific regulations. They include promoting research, protecting health, fostering investment and joint ventures, guaranteeing supply, controlling the peaceful use of nuclear materials, exercising property rights over certain special fissile materials, creating a common nuclear market, and establishing international relations in the civil nuclear field.
Titles III and IV regulate the institutions and fundingSince 1967, Euratom has shared executive bodies with the EU, although the division of powers is not identical to that established in the Union treaties: the European Parliament, for example, has a more limited role in this area, with primarily advisory functions. Furthermore, the Euratom Supply Agency is established as a separate body with its own legal personality and financial autonomy.
From a budgetary point of view, Euratom's administrative expenses are integrated into a shared single budget with the rest of the EU institutions, although R&D programs funded on the basis of the Euratom Treaty maintain a separate budget line to reflect their technical and legal specificity.
The Treaty also includes several annexes that specify important material areas. These detail, for example, the field of research related to nuclear energy referred to in Article 4, the industrial sectors relevant to Article 41, the advantages applicable to joint undertakings under Article 48, the list of goods and products covered by the chapter relating to the nuclear common market and the former initial research and teaching programme provided for in Article 215, now repealed.
These annexes, although sometimes overlooked, serve to operationalize general provisions of the Treaty and offer a fairly detailed map of the activities and sectors that fell under the umbrella of Euratom at the time of its signing, progressively adapting to technological and regulatory evolution.
Main missions of the Euratom Treaty
Among the missions assigned to Euratom is, first and foremost, the promotion of research and scientific cooperation in the nuclear field. The Treaty provides for the creation of a Joint Research Centre and promotes the exchange of technical information, with the aim of ensuring that advances are shared among Member States and do not remain isolated.
Another essential mission is the establishment and implementation of radiation protection standards Uniforms to safeguard the health of the population and exposed workers. This function has been decisive in shaping dose limits, radiological monitoring requirements, and safety criteria in the design and operation of facilities within the EU.
The Treaty also deals with facilitate investments necessary for the development of nuclear energy, promoting the creation of joint ventures and the establishment of basic facilities. This translates into a favorable framework for shared research projects, fuel cycle infrastructure, and advanced training centers.
A key element is the common policy of supply of minerals and radioactive fuelsThis aims to guarantee a regular and equitable supply for all users in the Community. To this end, the Euratom Supply Agency was created, which oversees supply contracts and ensures that there is no unjustified discrimination between Member States.
Furthermore, Euratom is entrusted with the task of to control the proper and peaceful use of nuclear materialsIts safeguards system, supported by its own body of inspectors, allows for accounting and physical checks to be carried out at all nuclear facilities in the Community, with a view to preventing any diversion towards military programs.
Institutional structure and annexes of the Euratom Treaty
At the institutional level, Euratom has shared, since the 1967 Merger Treaty, the executive bodies with the European Unionbut with a different distribution of powers. In the nuclear field, the European Parliament does not exercise the co-decision-making power it has in other areas, its role being largely reduced to issuing opinions and indirect political control.
The Euratom Supply Agency is configured as a specific body with its own legal personality and financial autonomy, subject to the supervision of the European Commission. Its role is central to nuclear supply policy and to ensuring transparency and fairness in access to critical raw materials.
From a budgetary point of view, Euratom's administrative expenses are integrated into a shared single budget with the rest of the EU institutions, although R&D programs funded on the basis of the Euratom Treaty maintain a separate budget line to reflect their technical and legal specificity.
The Treaty also includes several annexes that specify important material areas. These detail, for example, the field of research related to nuclear energy referred to in Article 4, the industrial sectors relevant to Article 41, the advantages applicable to joint undertakings under Article 48, the list of goods and products covered by the chapter relating to the nuclear common market and the former initial research and teaching programme provided for in Article 215, now repealed.
These annexes, although sometimes overlooked, serve to operationalize general provisions of the Treaty and offer a fairly detailed map of the activities and sectors that fell under the umbrella of Euratom at the time of its signing, progressively adapting to technological and regulatory evolution.
The Nuclear Law Committee (NLC) and regulatory harmonization
Alongside the network of treaties and organizations, the work of technical bodies such as the Nuclear Law Committee (NLC), linked to the NEA. Its main mission is the creation and consolidation of legal frameworks, both national and international, that are stable, coherent and compatible with the peaceful use of nuclear energy.
The NLC focuses on promoting the modernization and harmonization of nuclear legislation of the various countries, so that their domestic laws adequately reflect the commitments made in major international treaties. This includes everything from the regulation of civil liability to the safety of facilities, the transport of radioactive material, and waste management.
In addition to its regulatory role, the Committee aims to act as reference in information and training on nuclear law, facilitating the exchange of experiences among regulatory authorities, ministries, operating companies, and academic experts. This educational role is key to reducing knowledge gaps between countries with a long nuclear tradition and others that are starting civilian programs.
In practice, the work of the NLC complements and reinforces the frameworks created by the IAEA and by treaties such as Euratom, helping to ensure that the international legal mosaic does not fragment into irreconcilable regimes, but rather moves towards a certain convergence of standards.
This entire regulatory ecosystem—multilateral treaties, specific agreements, specialized organizations, and expert committees—constitutes a dense legal framework for civil nuclear energyThanks to it, the long-term operation of power plants, protection against accidents, liability for damages and the non-proliferation of weapons find common ground where States can cooperate, settle responsibilities and strengthen their internal systems without losing sight of the international dimension of the risks and benefits involved.
